True, I was looking at that too. The rear end of the black rubber seal on the tail piece is very dry. The pedestal is slim enough that I can't see or feel the front of that rubber seal without dissassembling the whole thing. Any other way to check it? The 1.25"-1.5" adapter washer was clearly leaking--had water visibly welling up.

: Since that connection is probably directly below the brass drain fitting, be certain that the water you see is not coming from around the connection at the sink or where the tailpiece is screwed into the drain fitting.